Digester for sulphite wood pulp



Dec. 16, 1930. E. MORTERUD DIGESTER FOR SULPHITE WOOD PULP Fil ed Feb. 26, 1929 H I. l

Patented Eco. 16, 1930 mesa.

@JNITED STATES PATENT? -OFFICE EINAR MOR'IERUD, F TORDEBOD, NEAR MOSS, NORWAY DIGESTER FOR SULPHITE WOOD PULIB Application filed February 26, 1929, Serial No. 342,743, and in Norway January 25, 1929.

The present invention relates to digesters for sulphite wood pulp, and the object of the invention is to provide a digester for the purpose specified, having simple and effective means for circulating through the digester liquor which has been heated in a. heating apparatus located outside the digester.

In accordance with the present invention the means for effecting a circulation of the heated liquor through the digester consist in pipe lines mounted in the interior of the .digester and communicating at one end with intake and outlet openings respectively,% 10- cated adjacent" each other near the middle part of the digester and bein'gconnected at their opposite ends with sieve boxes located respectively near the lower and upper end of the digester.

Although it has been recognized for a long 29 time that it would be desirable to provide sulphite wood pulp digesters with means permitting the liquor to be circulated through the same, the construction of a digester satcorrosive nature of the liquor to be handled, as well as to. the considerable temperature differences existing between the liquor 30 pumped into and out of the digester.

By mounting the circulation pipes inside I a the digester in the manner which is described below in accordance with the present invention, the clrculatlon pipes, sieve boxes and the fastening means for the same may be manufactured of a non-corrosive steel alloy,

the use of which for this purpose is met by great difficulties owing to the extreme fragility of this material, particularly at all welded o1nts.

d In accordance with one feature of the present invention the circulation pipes communicating with the intake and outlet openings of the digester comprise at least two sections which are individually fastened to the diff" gester wall at one point only for each section,

and which fit loosely into each other without the use, of any kind of packing box or the boxes between the several sections of the circulation pipes may be dispensed with without any inconvenience, and as the pipe sections are each fastened to the digester wall at one point, it will be understood that they are all absolutely free to expand or contract in an axial direction without causing any stress isfying these requirements has been met with 5 certain difficulties owing to the extremely whatever at the fastening clamps or at welded joints.

' In accordance with the present invention the several sections of the circulation pipes are fastened to the digester wall by means of clamps, the shanks of which are secured to the sheet iron shell of the digester and which pass through the brick-lining thereof.

Besides the said fastening clamps for the pipe sections there are provided in accord.- ance with the present invention auxiliary fastening means for preventing, any movement of the pipe sections in a lateral direcprovided with a brick-lining 2 and having intake and outlet openings 3, 4 located adjacent each other near the middle part of the digester.

It will be understood that the heating and circulating means located outside the digester proper have nothing to do with the present invention, and that they may be arranged in a known manner so as to reverse the direction of the circulation so that either of. the openings 3 and 4 may be used as intake and outlet respectively.

Pipe sections 5 and 6 of non-corrosive like. v It has been found that by mounting the cir- 5 culationpipes inside the digester, packing steel communicate with the openings 3 and 4 and are secured to the digester shell 1 by means of tight fitting clamps 7 and 8, th

4 tening clamp secured to the gester.

shanks 9, 10 of which pass through the bricklining 2 of the digester and are secured to the digester shell adjacent the openings 3 and 4. At their opposite ends the pipes 5 and 6 fit loosely into pipe sections 11, 12, which are made in the form of sieve boxes and which are secured to the shell of the digester by means of tight fitting clamps 13, 14.

Besides the tight fitting clamps 7, 8 and 13, 14 an appropriate number of loose fitting clamps or guides 15 are provided in order to prevent lateral movement of the pipe sections. It is important that these clamps or guides 15 do not in any way impede axial movement of the pipe sections. Also as it has been stated above, it is very important that the connection between the several sections of each pipe is a loose fitting joint, as a possible leakage at these points is not in any way likely to cause disturbance in the,

operation, whereas such clogging as may take place in the case of an ordinary expansion joint or a packing box would be very likely to cause breakage of the fastening clamp shanks and the welded joints.

It will be understood that whereas each pipe according to the embodiment of the invention illustrated does only comprise two sections, it may be convenient in some cases to use pipes comprising three or more sections, each being secured to the digester shell at one point and fitting loosely into each other.

In order to protect the brick-lining of the digester in the immediate vicinity of the sieve boxes 11, 12, protection plates 16, 17 of a non-corrosive material are secured to the brick-lining under the said sieve boxes.

Claims: 1. A digester for sulphite wood pulp comprising a brick-lined sheet-iron shell having intake and outlet openings for circulatingheated digesting liquor, characterized by that the said intake and outlet openings which are located adjacent each other near the middle of the digester communicate with circulation pipes located inside the digester, each comprising at least two sections loosely fitted into each other and fastened to the digester shell at one point only by a tight fasshell of the di- 2. A digester for sulphite wood pulp comprising a brick-lined sheet iron shell having intake and outlet openings for circulating heated digesting liquor, characterized by that the said intake and outlet openings which are located adjacent each other near the middle of the digester communicate with circulation pipes located inside the digester,

each comprising at least two sections loosely fitted into each other and fastened tothe digester shell at one point only, means being provided at other points of said sections for preventing lateral movement thereof.

3. A digester for sulphite wood pulp comprising a -brick-lined sheet iron shell having intake and outlet openings for circulating heated digesting liquor, characterized by that the said intake and outlet openings which are located adjacent each other near the middle of the digester communicate .with circulation pipes located inside the digester, each com-' prising at least two sections loosely fitted into each other and fastened 'to the digester shell at one point only by tight fastening clamps secured tothe shell of the digester, loose fitting guiding clamps being provided at other points ofsaid sections for preventing lateral movement thereof. j

4. A digester for'sulphite wood, pulp comprising a brick-lined sheet iron shell having intake and outlet openings for circulating heated digesting liquor, characterized by that the said intake and outlet openings which are located adjacent each other near the middle of the digester communicate with circulation pipes located inside the digester and comprise at least two sections each of which is loosely fitted into the other and is fastened to the digester wall at one point only, the end sections of each circulation pipe consisting in a sieve box into the open end of which the end of the adjacent pipe section is loosely fitted.

5. In a digester for sulphite wood pulp a sheet iron shell, a brick-lining for the interior thereof, intake and outlet openings for circulating liquor through the contents of the digester, said intake and outlet openings .being located adjacent each other near the middle of the digester, circulation pipes comprising a plurality of sections fitting loosely into each other communicating with said intake and outlet openings and a single fastening, clamp for each pipe section secured to the digester shell and passing through the brick lining thereof.

6. digester for sulphite wood pulp comprising a brick-lined sheet iron shell, circulation pipes located inside said shell, said pipes'comprising at least two sections each of which is loosely fitted into the other and is fastened to the digester wall at one point only. 7 j

7 A digester for sulphite wood pulp comprising a brick-lined sheet iron shell, circulation pipes located inside said shell, said pipes comprising at least two sections loosely fitted into each other and fastened to thedigester shell at one point only by a .tight fastening clamp secured to the shell of the digester.

8. A digester for sulphite wood pulp comprisin a brick-lined sheet iron shell, circula-. tion pipes located inside said shell, said pipes other and fastened to the digester at other points of said sections for preventing lateral movement thereof.

9. A digester for sulphite wood pulp comprising a brick-lined sheet iron shell, circulation pipes located inside said shell, said pipes comprising at least two sections loosely fitted into each other and fastened to the digester shell at' one point only by tight fastening clamps secured to the shell of the digester, loose fitting guiding clamps being provided at other points of said sections for preventing lateral movement thereof.

10. A digester for sulphite wood pulp comprising a brick-lined sheet iron shell, circulation pipes located inside said shell, said pipes comprising at least two sections each of which is loosely fitted into the other and is fastened to the digester wall at one point only, the end sections of each circulation pipe consisting in a sieve box into the open end of which the end of the adjacent pipe section is loosely fitted.

11. A digester for sulphite Wood pulp comprising a brick-lined sheet iron shell, circular tion pipes located inside said shell, said pipes comprising a plurality of sections fitting loosely into each other communicating with said intake and outlet openings and a single fastening clamp for each pipe section secured to the digester shell and, passing through the brick-lining thereof.

In testimony whereof I afiix my signature.

EINAR MORTERUD. 

